British Airways has been urged to automatically compensate passengers caught up in the bank holiday disruption rather than wait for them to submit claims. In previous strike action, the airline has managed to minimise delays and cancellations.

European Union law allows those affected up to €600 (£524) in compensation and they can also claim for things such as hotels, meals and phone calls.

Consumer group Which? has said in a letter to British Airways chief executive, Alex Cruz that to “reduce the burden on passengers” and to not create “further damage to BA’s reputation”, the airline should issue statutory compensation to all those who were affected.

“Given the scale of the problem BA has experienced, we strongly believe it is only right that you do more than the legal minimum”. Chaos occurred when British Airways’ two main data centers lost juice and an uncontrolled reboot of the system shut down the entire IT system, resulting in the loss of all information about flights, baggage and passengers. It blamed a power surge that knocked out its computer system, disrupting flight operations, call centers and its website.

The airline has been accused by the insurance industry of passing affected customers from “pillar to post” after it advised that “in the first instance” they should claim against their insurance policies.

A BA spokeswoman said: “As on the previous dates when Unite called strikes of mixed fleet cabin crew, we will fly all our customers to their destinations”.

BA apologised for the “difficulties and frustration customers faced” and made assurances they would honour compensation obligations.